Intel i7-660LM CN80617004857AA User Manual

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Datasheet

Dual-Channel Symmetric mode, also known as interleaved mode, provides maximum 

performance on real world applications. Addresses are ping-ponged between the 

channels after each cache line (64-byte boundary). If there are two requests, and the 

second request is to an address on the opposite channel from the first, that request can 

be sent before data from the first request has returned. If two, consecutive cache lines 

are requested, both may be retrieved simultaneously, since they are ensured to be on 

opposite channels. Use Dual-Channel Symmetric mode when both Channel A and 

Channel B SO-DIMM connectors are populated in any order, with the total amount of 

memory in each channel being the same.

When both channels are populated with the same memory capacity and the boundary 

between the dual-channel zone and the single channel zone is the top of memory, IMC 

operates completely in Dual-Channel Symmetric mode. 

The DRAM device technology and width may vary from one channel to the other. 

This mode trades performance for system design flexibility. Unlike the previous mode, 

addresses start at the bottom of Channel A and stay there until the end of the highest 

rank in Channel A, and then addresses continue from the bottom of Channel B to the 

top. Real world applications are unlikely to make requests that alternate between 

addresses that sit on opposite channels with this memory organization, so in most 

cases, bandwidth is limited to a single channel.

This mode is used when Intel Flex Memory Technology is disabled and both Channel A 

and Channel B SO-DIMM connectors are populated in any order with the total amount 

of memory in each channel being different. 

C H   B

C H   A

C H   B

C H   A

B

B

C

B

B

C

B

B

C

B   –   T h e   la rg e s t  p h y s ic a l  m e m o ry   a m o u n t  o f  th e   s m a lle r  s iz e   m e m o ry   m o d u le
C   –   T h e   re m a in in g   p h y s ic a l  m e m o ry   a m o u n t  o f  th e   la rg e r  s iz e   m e m o ry   m o d u le